Metformin has long been a trusted medication for type-2 diabetes, but recent research is opening a new chapter, exploring how it might influence the brain itself. A 2025 study from Baylor College of Medicine found that metformin doesn’t only act on the liver or gut; part of its glucose-lowering effect seems to come from a previously unknown pathway in the brain’s hypothalamus. The drug appears to switch off a small protein called Rap1 in a region known to regulate metabolism.
This discovery suggests metformin may modify brain activity, and by doing so, could influence whole-body metabolism in new ways. Meanwhile, some earlier research in animals has given hope that metformin might support brain health under stress. For instance, another recent study showed that metformin helped lessen brain inflammation and memory impairments in a model of chemically induced neurodegeneration.
But it isn’t all straightforward. A large review of human studies found no clear evidence that metformin consistently improves cognitive performance or protects against dementia. What seems likely is that metformin’s effect on the brain may depend heavily on individual biology, age, and metabolic state.
So what does this mean for us?
Metformin might offer more than blood-sugar control, potentially influencing brain metabolism and health. Still, until larger, rigorous human trials confirm these effects, it remains a promising possibility, not a prescription for enhanced brain power.
MBH/PS